Questions tagged [three-dimensional]
This tag is used for geometric puzzles, if one wants to stress that the setting is not 2-dimensional but 3-dimensional.
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Identical cubes in a sphere
Suppose that you have a sphere of radius 10cm. At most how many cubes of side 1cm can you fit in the sphere such that:
A cube can touch another cube (share a face, an edge or a point) but cannot ...
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Packing 25 three-dimensional N pentominoes into a 5x5x5 cube
The puzzle contains 25 identical pieces that look like this:
To be explicit, the piece is composed of five cubes. In the picture, three cubes form the base, and two cubes form the overhang.
The goal ...
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Dramatic follow-up 3D masyu problem
This is follow-up problem for Another four 3D masyu
Your little dog has been abducted by aliens, and they will do unthinkable things to it. That is unless you provide solutions for problems C and D, ...
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Another four 3D masyu
This puzzle is inspired and descended from Brain-breaking 3D masyu
Here the exact copy of rules, for convenience:
This is a three-dimensional masyu puzzle.1 The five squares depict the layers of a $...
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You won't believe what John's hostesses discovered
This is a three-dimensional crossword. The seven grids below depict the layers of a 7x7x7 cube. "Across" and "down" clues work like in normal crosswords, and "away" clues ...
- 78.9k
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Build a slanted pyramid with ten L-shaped blocks
Consider the following L-shaped 3-dimensional object made up of three unit cubes joined at their faces:
Use 10 of the above L-shaped pieces to make the following shape:
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Can 42 1x2x4 cuboids be packed into a 7x7x7 cube?
Can 42 1x2x4 cuboids be packed into a 7x7x7 cube without cutting any of them? Assume that all cuboids have their axes parallel to the axes of the big cube. I tried using https://www.jaapsch.net/...
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Filling a 5x5x5 grid
Inspired by this. On each line to the left is the position of a word, and to the right is the "snyptic clue" not a cryptic clue (duh) for the word, along with the word's length. The 5x5x5 ...
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Anyone up for a 3x3x3 Hidato?
So, I have been pretty evil with how I make Hidato puzzles lately, with there being no numbers. To make up for it, I have decided to make a 3x3x3 Hidato for you all. Yes you read that right. I made a ...
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A sudokey and 14 messages
This puzzle is part of the Monthly Topic Challenge #15: Multi Puzzle — two (or more) puzzles in one.
Remarks:
Feel free to post partial solutions.
This is a multi-puzzle: If you found the titular 14 ...
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The Triangular Cannonball Problem [closed]
How many ways are there to stack an equilateral triangle of cannonballs into a tetrahedron of cannonballs? In other words, how many positive integers are both triangular and tetrahedral?
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Assemble n^3 cubes into n different n×n×n larger cubes [duplicate]
You might have seen this question before:
Goal: Paint 27 cubes using three colors (for example, red, yellow, and blue), so that you can form a 3x3x3 cube with all surfaces in red (for example), a ...
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Packing a 3xMxN-box with copies of a single tetracube
There seems to be no solution for packing a 3xMxN-box with copies of this tetracube.
Does anybody know of a proof that this is impossible or is this still an open question?
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12 piece cube packing puzzle
Consider the following hexacube (made from 6 unit cubes):
GOAL:
Pack a 3 x 3 x 3 cube using three of these hexacubes plus nine unit cubes.
This puzzle comes from: https://puzzlewillbeplayed.com/333/...
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Find all the objects from their shadows
In my previous puzzle I asked you to derive the 3D object that casts 3 different shadows: circle, square and an equilateral triangle.
This is a more general version of the puzzle. If we limit ...
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